1. Field of Invention
The present invention relates to a silicone composition emulsion and a method for preparing the same, and more particularly, to a method for improving the stability of a high-viscosity silicone composition emulsion dispersion, which is related to the preparation of fine chemical additives, and is in the field of fine chemical preparation technology.
2. Related Art
The silicone dispersion, i.e., emulsion, has very wide application range, and is applicable in textile finishing agents, fabric softeners, antiperspirants, defoamers, release agents, and so on. The high-viscosity polysiloxane is an important component in shampoos. The composition of white carbon black and high-viscosity polysiloxane has important application in sealing, lubrication, insulation, anti-corrosion protection, and it also has excellent anti-foaming performance in foam control.
The silicone emulsion is mainly divided into two types, that is, water in oil (W/O) and oil in water (O/W). The silicone emulsion used in the fields of textiles and cosmetics is substantially the O/W type. The preparation of the O/W type silicone emulsion mainly includes two methods: the first one is a polymerization method, that is, silicone monomers are polymerized in the presence of a catalyst, an initiator, and a surfactant, for example, for hydroxyl silicone oil emulsion, and the second one is a mechanical method, that is, components for preparing the emulsion, including oil-phase component, emulsifier, water, stabilizer, are dispersed through heating and stirring, mechanical shearing, colloid milling, homogenization.
It is difficult to emulsify and disperse a high-viscosity silicone composition into water, which is described in Patent CN1807512. The functions of the silicone emulsion are related to many properties of the emulsion itself, for example, temperature stability, shear resistance, dilution stability, and storage stability of the emulsion, and in U.S. Pat. No. 6,001,887, methods for testing the stability of the emulsion are reported. As for defoamers, if a silicone defoamer emulsion having poor stability is used in dyeing of cotton and chemical fibers to eliminate harmful foams, “silicone spots” will be formed on the cloth, thus the efficiency of dyeing and the quality of the final product are seriously affected. Therefore, the stability of the silicone emulsion is very important.
In U.S. Pat. No. 4,853,474, the low-temperature resistance is improved with crosslinked silicone-polyether, but in this method, the crosslinking degree of the silicone polyether itself is difficult to be controlled, so the uniform stability of the emulsion cannot be ensured. In U.S. Pat. No. 5,451,692, alkyl silicone-polyether is applied in the preparation of W/O type emulsion, and the compatibility with the oil phase component is improved through the introduction of the alkyl group. In EP-A-163541, it is introduced in studying defoamers that, the preparation of the high-viscosity polysiloxane emulsion is difficult, the cost is very high, and the effect is poor.
Through a lot of experiments, the inventors of the present invention have found that, adding a low-molecular-weight polysiloxane into a high-viscosity silicone composition in dispersing the composition is benefit to the preparation of a stable emulsion.